package com.yicheng.springcloud.lb;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

@Component
public class MyLb implements LoadBalancer{

    private AtomicInteger atomicInteger = new AtomicInteger(0);

    //获取下一次运行的数字
    public final int getAndIncrement(){
        int current;
        int next;
      do{
          current = this.atomicInteger.get();
          next = current >= Integer.MAX_VALUE ? 0 : current+1;
      }while (!this.atomicInteger.compareAndSet(current,next));
        System.out.println("------------next:"+next);
        return next;
    }

    @Override
    public ServiceInstance instance(List<ServiceInstance> serviceInstances) {
        int index = getAndIncrement() % serviceInstances.size();
        return serviceInstances.get(index);
    }

}
